Sow spinach outdoors March to May for a spring crop, or August to September for autumn and overwintering pickings, harvesting May through November. Direct-sow little and often — spinach dislikes root disturbance — and avoid June–July sowings, when long days and heat trigger bolting.
Last updated 4 July 2026
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Spinach is a fast-growing, nutritious leafy vegetable that thrives in the cool UK climate — ideal for spring and autumn harvests, and one of the best crops for gaps between seasons.
When to Sow Spinach in the UK
Spinach is a cool-season crop that bolts quickly in summer heat. Sow in two main windows: February to May for spring harvests, and August to September for autumn and overwintering crops. The RHS notes that spinach prefers cool conditions and can be overwintered under cover for early spring pickings.
Spinach Sowing & Harvest Calendar
| Task | Timing | Notes |
|---|---|---|
| Sow outdoors (spring) | March – May | Direct sow, 2.5cm deep |
| Sow outdoors (autumn) | August – September | For overwintering and early spring pickings |
| Harvest | May – November | Avoid June–July sowings — long days and heat trigger bolting |
Sowing and Growing
Sow seeds 2.5cm deep in drills 30cm apart. Thin seedlings to 15cm apart for baby leaf harvests, or 30cm for mature leaves. Water consistently — drought stress causes immediate bolting. In hot weather, provide light shade and water daily. Spinach grows well in containers at least 20cm deep.
Preventing Bolting
Spinach bolts (runs to seed) rapidly in heat or drought. Key prevention: sow in spring and autumn rather than midsummer; choose slow-bolting varieties; keep soil consistently moist; harvest regularly to reduce plant stress.
Top UK Varieties
Medania
Reliable, slow-bolting variety with round, smooth leaves. Good for both spring and autumn sowing. AGM winner.
Emilia
Compact leaves ideal for baby leaf harvests. Very quick from sowing. Good bolt resistance for summer growing.
Giant Winter
Hardy variety for autumn sowing and overwintering. Large, crinkled leaves. Harvests from late winter through spring.
Harvesting
Begin harvesting outer leaves when plants are 15–20cm tall. Cut-and-come-again harvesting keeps plants productive for longer. Pick in the morning when leaves are crisp and cool. Harvest the whole plant once it shows signs of bolting (central stem elongating).
Common Spinach Mistakes
Overcrowding plants below 15cm apart encourages downy mildew in humid weather — space out and avoid evening watering to keep foliage dry overnight. Leaving weeds around seedlings gives slugs cover; keep beds weeded, especially early on. Unprotected seedlings are vulnerable to bird damage — net or fleece rows until plants are established. For the most bolt-resistant crop, look beyond the varieties above to Apollo AGM or Amazon AGM, both bred specifically to resist running to seed.
Plan Your Leaf Crop Succession
The SoilCommander UK Vegetable Garden Planner includes succession sowing guides for spinach, chard, kale, and all your leaf crops.
Get the Garden PlannerWhy does my spinach keep bolting?
Spinach bolts due to heat, drought, or long days. Sow in February–May and August–September rather than midsummer, choose slow-bolting varieties, and keep soil moist.
Can I grow spinach in summer in the UK?
It’s difficult. Spinach bolts rapidly in warm weather. For summer leaf crops, try Swiss chard, perpetual spinach, or New Zealand spinach — all far more heat-tolerant.
How do I overwinter spinach?
Sow a hardy variety like Giant Winter in August–September. Protect with cloches or fleece from November. Plants will pause growth in winter and resume in February, providing early spring pickings.
Browse sowing dates for all crops in the UK vegetable planting calendar or explore all UK vegetable growing guides.
Tools That Help With This Crop
Use these links when the guide moves from reading into sowing, planting, watering, and keeping the crop healthy.
Plan the next step
Use the printable UK Vegetable Garden Planner to turn this guide into sowing dates, bed layouts, and weekly garden tasks.